Sleek and Seamless Solution for Noisy Rooftop
The challenges
An historic site in inner‐city Glebe, Sydney, is being radically transformed via a $1.1b rejuvenation project by real estate group Mirvac.
Expected to be completed in 2019, the high profile Harold Park development will turn former Rozelle tram sheds into an industrial‐styled world-class venue alongside several modern apartment buildings featuring 1,250 new residences.As a Sydney icon, developers and local council were conscious of preserving the historical significance of the site while providing the highest quality standards of modern living via sustainable materials.
To this end, one issue faced by Mirvac was finding an aesthetically viable solution to prevent noise breakout from rooftop air conditioning units and ventilation systems above three luxury residential apartment buildings. The first solution was to fit a set of non‐acoustic louvres to constrain the breakout and redirect the sound, with unsatisfactory results. Not only were the heavy louvres unable to contain the noise, they proved more costly than expected and required expensive craning onto the rooftop.
The solutions
Recognising the issue and having worked with installers on previous projects, Pyrotek consultants stepped in with a more efficient solution for the remaining two towers. With full information at hand, Sorberpoly 2D AGC, ticked every box in terms of look, noise absorption, durability and cost efficiency. An extremely lightweight, compressible polyester acoustic insulation, Sorberpoly 2D offers superior sound absorption combined with exceptional durability, even in outdoor applications.
Installing Sorberpoly 2D panels was a superior solution in several ways. Firstly, the lightweight panels could be easily delivered to the rooftop in an elevator, eliminating the expense and time to crane the products into place. Also, installation of Sorberpoly 2D is a swift process due to its easy handling and ability to cut to size with scissors.
In terms of sustainability and environmental impact, Sorberpoly 2D delivered again. Made from 100% polyester fibres. Sorberpoly 2D is recyclable, completely non‐toxic, contains no irritants, features self‐draining hydrophobic properties to repel water and eliminate mildew, and won’t degrade or crumble over time.
Additionally, Mirvac specified the Soundlag® 4525C system for the buildings’ waste water pipes and duct work, to reduce disruptive noise transfer between apartments. Featuring 25mm flexible convoluted foam and a fire retardant aluminium facing, Soundlag 4525C is easily cut to size and taped around even the smallest pipes to create a noise‐tight seal.
The results
Pyrotek supplied 130 panels of Sorberpoly 2D, the project required 60mm density polyester at 1.2 x 2.4m. To augment the modern architectural lines of the building, Pyrotek’s consultants recommended aluminium glass cloth facing (AGC) in black. With a density of 220, the glass cloth finish provided the builders with their required building warranty, and further enhanced noise absorption compared to plain polyester board.
The SorberpolyTM 2D AGC panels were placed facing the noise source, laminated and nail glued to the framework of the HVAC units. A u‐cap was fixed to the top to send rainwater away from the material as a precautionary measure for the longevity of the product. An air gap behind the polyester further improves noise containment.
To finish, the sheets were joined using black glass cloth tape, no visible seams. The end result is a seamless black rooftop wall with superior noise inhibiting properties to protect the community and residents from rumbling and humming noise from the HVAC systems.
